Fix Typo in Metadata API Description (#51024)

### Fix Typo in Metadata API Description

#### Description:

This PR fixes a minor typo in the description of the Metadata API.

#### Changes:

- Fixed typo in the Metadata API description. 

**File:** `docs/02-app/01-building-your-application/05-optimizing/04-metadata.mdx`

**Old Sentence:**

> Next.js has a Metadata API that can used to define your application metadata (e.g. `meta` and `link` tags inside your HTML `head` element) for improved SEO and web shareability.

**New Sentence:**

> Next.js has a Metadata API that can be used to define your application metadata (e.g. `meta` and `link` tags inside your HTML `head` element) for improved SEO and web shareability.

This change helps improve the readability and understanding of the documentation for readers and users.

#### Checks:

- [x] Followed the Docs Contribution Guide
- [x] Linting passes (`pnpm build && pnpm lint`)

docs/02-app/01-building-your-application/05-optimizing/04-metadata.mdx

@@ -8,7 +8,7 @@ related:
     - app/api-reference/file-conventions/metadata
 ---
 
-Next.js has a Metadata API that can used to define your application metadata (e.g. `meta` and `link` tags inside your HTML `head` element) for improved SEO and web shareability.
+Next.js has a Metadata API that can be used to define your application metadata (e.g. `meta` and `link` tags inside your HTML `head` element) for improved SEO and web shareability.
 
 There are two ways you can add metadata to your application: